This PPT will let you know the basic information about the fuels, the octane number and the cetane number

1. FUELS,
OCTANE NO & CETANE NO
Prepared by :-
Abdul Kadir (110010119126)
Ripal Maravia (110010119036)

2. FUELS
 Each substance which gives energy after burning is
called fuel.
 Fuels are classification by sources;
a. Natural
b. Artificial
 Fuels are classification by phases;
a. Solid – coal, wood etc.
b. Liquid – petroleum products, alcohol, biofuel etc.
c. Gas – methane, buthane, hydrogen, biogas etc.

3.  Generally Liquid fuels are preferential
1. Energy per gram is too high
2. Fast conversion of chemical energy to thermal
energy
3. Easy mix with oxygen
4. No ash after combustion
5. Easy transport and storage
 Every liquid substance which provides the sufficient
thermal energy
can be used as a fuel for internal combustion engines.

4. OCTANE NO & CETANE NO
Cetane number (diesel fuel) and octane number
(gasoline) both measure the tendency of the fuel to
ignite spontaneously.
The cetane number refers to the eace with which
desel fuel ignites easily at a relatively low temperature.

5. Fuel Research Octane
Number
(ROM)
Motor Octane
Number
(MON)
Cetane
number
Boiling
point
(ºC)
Gasoline 92-98 80-90 0-5 37-205
Diesel -25 - 45-55 140-360
Methanol 106 92 5 65
Ethanol 107 89 5 79
Propane (LPG) 112 97 -2 -42.15
Methane (CNG) 120 120 0 -161.6
Octane and Cetane number of fuel

6. CETANE NUMBERS
 Higher cetane related with:
 improved combustion
 improved cold starting
 reduced noise, white smoke, HC, CO and
particulate emissions.

7. Gasoline Octane Rating
Measurement of the fuel’s ability to resist ignition
caused by pressure and heat resists knock or
ping.
Octane numbers give the antiknock value of
gasoline

8. Gasoline Octane Rating

9. Cetane Rating
Indicates the cold starting ability of diesel fuel
Most automakers recommend a cetane rating of
about 45
High cetane rating means the fuel will ignite easily
from heat and pressure and burn quickly

10. Cetane Rating

11. Fuel Ignition Quality
 The ignition characteristics of the fuel affect the
ignition
delay.
 The ignition quality of a fuel is defined by its cetane
number.
1) For low cetane fuels
2)For high cetane fuels

12. Fuels and Lubricants Lecture Notes 12